Ac compressor doesn’t come on
Pro
Joined: Jul 2017
Posts: 639
Likes: 95
From: Los Angeles, CA
2021 C4 of the Year - Modified Finalist
if you just replaced the orings, or recharged the system , disconnect the battery and reconnect it 5-10 minutes later...the ecm has to re-set......(sometimes helps to pray to the zr1 god).....Happened to me when I replaced the orings/recharged. Started up and A/c worked as it should...
Thread Starter
Advanced
Joined: Nov 2015
Posts: 83
Likes: 16
if you just replaced the orings, or recharged the system , disconnect the battery and reconnect it 5-10 minutes later...the ecm has to re-set......(sometimes helps to pray to the zr1 god).....Happened to me when I replaced the orings/recharged. Started up and A/c worked as it should...
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
Is the 1st ac light on the HVAC dash head unit flashing? if it is your low on Freon. You can get diagnostic help thru it.
Race Director
Joined: Feb 2002
Posts: 11,599
Likes: 1,053
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
Drifting
Joined: Jun 2013
Posts: 1,957
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From: Shell Point (Crawfordville) Florida
One more thing - If you have the 09 code because of low Freon, the compressor will not run, and you must have the compressor running to add Freon to the system. You must reset the computer by disconnecting the battery for 30 sec. or so, then reconnect it, then bypass the low pressure switch so the compressor runs, then add Freon. After you get enough in, you can reconnect the low pressure switch plug and add the rest up to the required amount needed.
